Method of Handling Long Term Evaluation Positioning Protocol Data and Related Communication Device

ABSTRACT

A method of handling long term evaluation positioning protocol (LPP) data for a communication device in a wireless communication system is disclosed. The method comprises setting that a first message of a non-access stratum (NAS) layer has higher transmission priority than a second message of a long term evaluation positioning protocol (LPP) layer.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/226,287, field on Jul. 17, 2009 and entitled “Methods fortransmitting LPP message in wireless communications system” and U.S.Provisional Application No. 61/233,842, field on Aug. 14, 2009 andentitled “Methods for transmitting LPP PDU in wireless communicationssystem” the contents of which are incorporated herein in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

A method utilized in a wireless communication and related communicationdevice are disclosed, and more particularly, to a method of handlinglong term evaluation positioning protocol data in a wirelesscommunication system and related communication device.

2. Description of the Prior Art

A long-term evolution (LTE) system, initiated by the third generationpartnership project (3GPP), is now being regarded as a new radiointerface and radio network architecture that provides a high data rate,low latency, packet optimization, and improved system capacity andcoverage. In the LTE system, an evolved universal terrestrial radioaccess network (E-UTRAN) includes a plurality of evolved Node-Bs (eNBs)and communicates with a plurality of mobile stations, also referred asuser equipments (UEs).

In the LTE system, a LTE Positioning Protocol (LPP) is set up betweenthe UE and an evolved serving mobile location centre (E-SMLC) fordetermining the result of the positioning for the UE. The LPP is a pointto point positioning protocol and supports positioning and locationrelated services (e.g. transfer of assistance data) for the UE accessingE-UTRAN. To avoid creating new positioning protocols for future accesstypes developed by 3GPP, and to enable positioning measurements forterrestrial access types other than E-UTRAN, LPP is in principleforward-compatible with other access types, even though restricted toE-UTRAN access.

According to the LTE specification for the LPP layer, several scenariosmay occur and are described as follows.

In the first scenario, a non-access stratum (NAS) layer and the LPPlayer are over a radio resource control (RRC) layer. Therefore, when aradio resource control (RRC) layer of the UE or the eNB has a LPPmessage and a NAS message to transmit, the LTE system does not clearlyspecify that RRC shall transmit the LPP message or the NAS messagefirst. In other words, how to prioritize transmission of the LPP messageand the NAS message is never concerned. If the NAS message (e.g. SERVICEREQUEST) transmission is delayed due to transmission of the LPP message,the call establishment (e.g. a mobile terminating call, a mobileoriginating call, or an emergency call) is delayed.

In the second scenario, the UE may transfer a LPP protocol data unit(PDU), to the E-SMLC via the eNB, whereas the E-SMLC may transfer theLPP PDU to the UE via the eNB. The UE or the eNB may not transmit LPPPDU successfully (e.g. interrupted by a handover or a RRC connectionre-establishment due to a radio link failure). The LTE system does notclearly define how to deal with this situation, thereby causing LPP PDUloss.

In the third scenario, the network may release a NAS signalingconnection with the UE. To allow the network to release the NASsignaling connection, the UE starts the timer T3440. When the timerT3440 expires, the UE releases NAS signaling connection and a RRCconnection. If the UE transmit the LPP PDU during a running period ofthe timer T3440, the LPP PDU transmission may be failed due to T3440expiry (i.e. RRC connection release).

SUMMARY OF THE INVENTION

A method of handling location service in a wireless communication systemis disclosed to solve the abovementioned problems.

A method of handling long term evaluation positioning protocol data fora communication device in a wireless communication system is disclosed.The method comprises setting that a first message of a non-accessstratum layer has higher transmission priority than a second message ofa long term evaluation positioning protocol layer.

A method of handling long term evaluation positioning protocol data fora mobile device in a wireless communication system is disclosed. Themethod comprises initiating a transmission for transmitting a protocoldata unit of a long term evaluation positioning protocol layer of themobile device, to a first base station of the wireless communicationsystem, and retransmitting the LPP PDU to the first base station or asecond base station when the transmission is failed.

A method of handling long term evaluation positioning protocol data fora network, e.g. an eNode B or a Mobility Management Entity (MME) in awireless communication system is disclosed. The method comprisesreceiving a protocol data unit of a long term evaluation positioningprotocol layer of an evolved serving mobile location centre of thewireless communication system, initiating a transmission fortransmitting the LPP PDU to a mobile device of the wirelesscommunication system, and indicating that the LPP PDU transmission isfailed to the E-SMLC when the transmission is failed.

A method of handling long term evaluation positioning protocol data fora network in a wireless communication system is disclosed. The methodcomprises initiating a transmission for transmitting a protocol dataunit of a long term evaluation positioning protocol layer to a mobiledevice of the wireless communication system via a first base station ofthe wireless communication system when a re-establishment of thecommunication layer lower than the LPP layer, a handover, or a radioresource control connection re-establishment occurs, and retransmittingthe LPP PDU to the mobile device via a second base station when thetransmission is failed, wherein the mobile device connects to the secondbase station after the mobile device performs the handover, or the RRCconnection re-establishment successfully.

A communication device of a wireless communication system for handlinglong term evaluation positioning protocol (LPP) data is disclosed. Thecommunication device comprises means for generating a first message of anon-access stratum (NAS) layer of the communication device and a secondmessage of a long term evaluation positioning protocol (LPP) layer ofthe communication device, and means for setting that the first messageof the NAS layer has higher transmission priority than the secondmessage of the LPP layer.

A mobile device of a wireless communication system for handling longterm evaluation positioning protocol (LPP) data is disclosed. The mobiledevice comprises means for initiating a transmission for transmitting aprotocol data unit (PDU) of a long term evaluation positioning protocol(LPP) layer of the mobile device, to a base station of the wirelesscommunication system, and means for retransmitting the LPP PDU to thebase station when the transmission is failed.

A base station of a wireless communication system for handling long termevaluation positioning protocol (LPP) data is disclosed. The basestation comprises means for receiving a protocol data unit (PDU) of along term evaluation positioning protocol (LPP) layer of an evolvedserving mobile location centre (E-SMLC) of the wireless communicationsystem, means for initiating a transmission for transmitting the LPP PDUto a mobile device of the wireless communication system, and means forindicating that the LPP PDU transmission is failed to the E-SMLC whenthe transmission is failed.

An evolved serving mobile location centre (E-SMLC) of a wirelesscommunication system for handling long term evaluation positioningprotocol (LPP) data is disclosed. The E-SMLC comprises means forinitiating a transmission for transmitting a protocol data unit (PDU) ofa long term evaluation positioning protocol (LPP) layer to a mobiledevice of the wireless communication system via a first base station ofthe wireless communication system when a re-establishment of thecommunication layer lower than the LPP layer, a handover, or a radioresource control (RRC) connection re-establishment occurs, and means forretransmitting the LPP PDU to the mobile device via a second basestation when the transmission is failed, wherein the mobile deviceconnects to the second base station after the mobile device performs thehandover, or the RRC connection re-establishment successfully.

These and other objectives of the present disclosure will no doubtbecome obvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred examples that areillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a schematic diagram of an exemplary wirelesscommunication system.

FIG. 2 illustrates a schematic diagram of an exemplary communicationdevice.

FIG. 3 illustrates a schematic diagram of exemplary program code.

FIG. 4-8 are flowcharts of exemplary processes.

DETAILED DESCRIPTION

Please refer to FIG. 1, which illustrates a schematic diagram of awireless communication system 10 according to an example. Briefly, thewireless communication system 10 is composed of a network and aplurality of mobile devices. The wireless communication system 10 can bean LTE (long-term evolution) system, LTE-Advanced system or any othersimilar network system. In the LTE system, the network can be referredas a EUTRAN (evolved-UTRAN) comprising a plurality of eNBs (e.g. basestations) or a core network entity (e.g. Mobility Management Entitycalled MME), whereas the mobile devices are referred as to userequipments (UEs). The UEs can be devices such as mobile phones, computersystems, etc. This terminology will be used throughout the applicationfor ease of reference. However, this should not be construed as limitingthe disclosure to any one particular type of network. In some examples,the network and the UE may be seen as a transmitter or receiveraccording to transmission direction, e.g., for uplink (UL), the UE isthe transmitter and the network is the receiver, and for downlink (DL),the network is the transmitter and the UE is the receiver.

FIG. 2 illustrates a schematic diagram of an exemplary communicationdevice 20. The communication device 20 can be the mobile device or thenetwork (e.g. a base station or an evolved serving mobile locationcentre (E-SMLC)) shown in FIG. 1, but is not limited herein. Thecommunication device 20 may include a processing means 200 such as amicroprocessor or Application Specific Integrated Circuit (ASIC), astorage unit 210 and a communication interfacing unit 220. The storageunit 210 may be any data storage device that can store program code 214,for access by the processing means 200. Examples of the storage unit 210include but are not limited to a subscriber identity module (SIM),read-only memory (ROM), flash memory, random-access memory (RAM),CD-ROMs, magnetic tape, hard disk, and optical data storage device. Thecommunication interfacing unit 220 is preferably a radio transceiver andcan exchange wireless signals with the network according to processingresults of the processing means 200.

Please refer to FIG. 3, which illustrates a schematic diagram of theprogram code 214 for the LTE system according to an example. The programcode 214 includes program code of multiple communications protocollayers, which from top to bottom are a LTE positioning protocol (LPP)layer 300, a non-access stratum (NAS) layer 310, a radio resourcecontrol (RRC) layer 320, a packet data convergence protocol (PDCP) layer330, a radio link control (RLC) layer 340, a medium access control (MAC)layer 350 and a physical (PHY) layer 360. The LPP layer 300 supportspositioning and related location services for the UE accessing theE-UTRAN, and is intended to enable positioning functionality for LTEusing a multiplicity of different position methods, e.g. a cell identity(ID) based method, an observed time difference of arrival (OTDOA)method, or a assisted Global Navigation Satellite System (A-GNSS)method.

Please refer to FIG. 4, which illustrates a flowchart of an exemplaryprocess 40. The process 40 is utilized in a communication device (e.g.the UE or the base station) for handling LPP data, where the UE can bethe mobile device of FIG. 1. The process 40 may be compiled into theprogram code 214 and includes the following steps:

Step 400: Start.

Step 410: Set that a first message of a NAS layer has highertransmission priority than a second message of a LPP layer.

Step 420: End.

According to the process 40, when the UE has the LPP message and the NASmessage to transmit, the UE transmits the NAS message first. That is,the UE sets the NAS messages as higher priority than the LPP PDU. TheNAS message is usually used for service initiation (e.g. a mobileterminating call, or a mobile originating call), and shall betransmitted prior to the LPP message, thereby avoiding NAS messagetransmission postponement that causes service delay.

Ways for LPP PDU transmission are described as follows. In the firstmethod, the UE transmits the LPP PDU and NAS message on signaling radiobearer 2 (SRB2). In the second method, the UE establishes a new SRB totransmit LPP PDU. The new SRB (e.g. SRB3) has a logical channel withlower priority than SRB2. More specifically, the UE RRC may receive aRRC message for configuring the SRB3 from a serving eNB RRC, and thenestablishes the SRB3 according to the RRC message. The RRC message maybe an RRCConnectionSetup message or an RRCConnectionReconfigurationmessage. In the third method, the UE sends the NAS message on SRB1 andthe LPP PDU on SRB 2, and the LPP PDU is forbidden to transmit on SRB1.Please note that, the SRB1 has higher logical channel priority than theSRB2, and a first transmission on the SRB1 has higher transmissionpriority than a second transmission on the SRB2. Logical channelprioritization shall be well-known in the art, so it is not givenherein. In the fourth method, the UE transmits the LPP PDU and NASmessage on the SRB1 if there is only SRB1 established (i.e. no SRB2).

Please refer to FIG. 5, which illustrates a flowchart of an exemplaryprocess 50. The process 50 is utilized in a UE for handling LPP data,where the UE can be the mobile device of FIG. 1. The process 50 may becompiled into the program code 214 and includes the following steps:

Step 500: Start.

Step 510: Initiate a transmission for transmitting a PDU of a LPP layerof the UE, to a base station of the wireless communication system.

Step 520: Retransmit the LPP PDU to the base station when thetransmission is failed.

Step 530: End.

According to the process 50, when the UE does not transmit the LPP PDUsuccessfully due to a re-establishment of a communication layer lowerthan the LPP layer, a handover procedure or a RRC connectionre-establishment procedure (e.g. radio link failure), the UE retransmitsthe LPP PDU after the UE performs the re-establishment of thecommunication layer, the handover or the RRC connection re-establishmentsuccessfully. Please note that, the LPP PDU retransmission may be or notbe exactly the same as the LPP PDU transmission.

Moreover, the re-establishment of the communication layer may be a RLCre-establishment or a PDCP re-establishment. In addition, the handovermay be an intra-radio access technology (RAT) handover. That is, thehandover is the intra-LTE handover since the LPP layer is developed inthe LTE system. On the other hand, if the handover is an inter-RAThandover, the UE does not retransmit the LPP PDU unless the target RATsupports LPP. Furthermore, if the LPP PDU contains old measurementresults, the UE does not retransmit the LPP PDU. For example, the UE ishandover to another base station, but the LPP PDU contains measurementresults associated with the original base station. In this situation,the UE shall not retransmit the LPP PDU to the connected base stationafter handover since the LPP PDU including old measurement results maynot be valid.

Take an example based on the process 50. The UE may fail in transmittingthe LPP PDU to the base station when the re-establishment of thecommunication layer lower than the LPP layer, the handover, or the RRCconnection re-establishment of the mobile device occurs. The UE RRCretransmits the LPP PDU after the UE performs the re-establishment ofthe communication layer (e.g. the RLC layer or the PDCP layer), thehandover or the RRC connection re-establishment successfully.Alternatively, the RRC layer may indicate to the LPP layer that the LPPPDU transmission is failed, and indicates to the LPP layer that there-establishment of the communication layer, the handover, or the RRCconnection re-establishment is performed successfully. After that, theLPP layer retransmits the LPP PDU when the RRC layer is indicated thatthe re-establishment of the communication layer, the handover, or theRRC connection re-establishment is performed successfully.

Or, the UE LPP starts a timer when transmitting the LPP PDU to the lowerlayer, retransmits the LPP PDU upon the timer expiry. If the UE RRCtransmits the LPP PDU successfully, the UE RRC indicates to the UE LPPthe LPP PDU transmission successes, and the UE LPP stops the timer.Besides the LPP layer and RRC layer are utilized to retransmit the LPPPDU, the UE PDCP retransmits the LPP PDU after the UE performs there-establishment of the communication layer, the handover, or the RRCconnection re-establishment successfully.

Please note that, the UE may transmit or retransmit the LPP PDU to thebase station on a SRB other than SRB1 and SRB2. Establishment for theSRB can be referred from above, so it is not given herein.

Based on the process 50, the UE knows how to deal with failure of LPPPDU transmission due to the lower layer re-establishment, the handover,or the RRC connection re-establishment, thereby avoiding LPP PDU loss.

Please refer to FIG. 6, which illustrates a flowchart of an exemplaryprocess 60. The process 60 is utilized in a network for handling LPPdata. The process 60 may be compiled into the program code 214 andincludes the following steps:

Step 600: Start.

Step 610: Receive a PDU of a LPP layer of an evolved serving mobilelocation centre (E-SMLC) of the wireless communication system.

Step 620: Initiate a transmission for transmitting the LPP PDU to a UEof the wireless communication system.

Step 630: Indicate that the LPP PDU transmission is failed to the E-SMLCwhen the transmission is failed.

Step 640: End.

According to the process 60, the network may fail in transmitting theLPP PDU received from the E-SMLC, to the UE when the re-establishment ofthe communication layer lower than the LPP layer, the handover, or theRRC connection re-establishment (e.g. the network cannot detect the UE)of the UE occurs. Therefore, the network indicates that the LPP PDUtransmission is failed to the E-SMLC. Thus, the E-SMLC can determinewhether to retransmit the LPP PDU or not.

Please note that, the handover may be an intra-LTE handover. Moreover,if the UE reconnects to a first base station of the network after thehandover or the RRC connection re-establishment procedure (namely the UEis not handover or connected to other base station), the first basestation does not indicate to the E-SMLC that the LPP PDU transmissionfailed, but retransmits the LPP PDU to the UE after the UE performs there-establishment of the communication layer lower than the LPP layer,the handover, or the RRC connection re-establishment successfully. Inaddition, the first base station may utilize the PDCP layer of the firstbase station to retransmit the LPP PDU to the UE after the UE performsthe re-establishment of the communication layer lower than the LPPlayer, the handover, or the RRC connection re-establishmentsuccessfully.

On the other hand, if the UE connects to a second base station of thenetwork after the handover or the RRC connection re-establishmentprocedure, the first base station forwards the LPP PDU to the secondbase station, so that the second base station retransmits the LPP PDU tothe UE after the UE performs the re-establishment of the communicationlayer lower than the LPP layer, the handover, or the RRC connectionre-establishment successfully.

Please refer to FIG. 7, which illustrates a flowchart of an exemplaryprocess 70. The process 70 is utilized in an E-SMLC for handling LPPdata. The process 70 may be compiled into the program code 214 andincludes the following steps:

Step 700: Start.

Step 710: Initiate a transmission for transmitting a PDU of a LPP layerto a UE of the wireless communication system via a first base station ofthe wireless communication system when a re-establishment of thecommunication layer lower than the LPP layer, a handover, or a RRCconnection re-establishment occurs.

Step 720: Retransmit the LPP PDU to the UE via a second base stationwhen the transmission is failed, wherein the UE connects to the secondbase station after the UE performs the handover or the RRC connectionre-establishment successfully.

Step 730: End.

According to the process 70, the E-SMLC transmits the LPP PDU to the UEvia the first base station. If the first base station does not transmitthe LPP PDU successfully due to the re-establishment of thecommunication layer lower than the LPP layer, the handover procedure orthe RRC connection re-establishment procedure, the E-SMLC retransmitsthe LPP PDU to the UE via the second base station to which the UEconnects after the handover, or the RRC connection re-establishment,thereby avoiding LPP PDU loss. Please note that, the first base stationbe may the same as the second base station if the UE is handover to thefirst base station, or the UE performs the RRC connectionre-establishment to the first base station.

The abovementioned handover is an intra-RAT handover (e.g. intra-RAThandover). On the other hand, if the handover is an inter-RAT handoverand the target RAT does not support LPP, the E-SMLC does not retransmitthe LPP PDU to the UE.

Please refer to FIG. 8, which illustrates a flowchart of an exemplaryprocess 80. The process 80 is utilized in a UE for handling LPP data,where the UE can be the mobile device of FIG. 1. The process 80 may becompiled into the program code 214 and includes the following steps:

Step 800: Start.

Step 810: Maintain a RRC connection with a network of the wirelesscommunication system when an LPP transmission is in process.

Step 820: End.

According to the process 80, the UE maintains the established RRCconnection when the LPP transmission is in process. For example, whenthe LPP transmission is ongoing, the UE keeps the established RRCconnection even though a timer T3440 for releasing the RRC connection ora NAS signaling connection expires. In other words, the UE does notrelease the RRC connection when the LPP transmission is in process,thereby avoiding the LPP transmission failure.

One way to maintain the established RRC connection during running of thetimer T3440 is described as following. The UE may keep the establishedRRC connection via stopping the timer T3440 when the LPP transmission isongoing. Therefore, the UE does not release the RRC connection, so as tocontinue the LPP transmission.

Alternatively, before starting the timer T3440, the UE may check whetherthe LPP transmission is in process. If no LPP transmission is inprocess, the UE starts the timer T3440. Otherwise, the UE does not startthe timer T3440.

Please note that, the abovementioned steps of the processes includingsuggested steps can be realized by means that could be hardware,firmware known as a combination of a hardware device and computerinstructions and data that reside as read-only software on the hardwaredevice, or an electronic system. Examples of hardware can includeanalog, digital and mixed circuits known as microcircuit, microchip, orsilicon chip. Examples of the electronic system can include system onchip (SOC), system in package (Sip), computer on module (COM), and thecommunication device 20.

In conclusion, the exemplary method and means are provided to handle theLPP PDU with the transmission priority, and transmission failure aspect.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the disclosure. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

1. A method of handling long term evaluation positioning protocol (LPP)data for a communication device in a wireless communication system, themethod comprising: setting that a first message of a non-access stratum(NAS) layer has higher transmission priority than a second message of along term evaluation positioning protocol (LPP) layer.
 2. A method ofhandling long term evaluation positioning protocol (LPP) data for amobile device in a wireless communication system, the method comprising:initiating a transmission for transmitting a protocol data unit (PDU) ofa long term evaluation positioning protocol (LPP) layer of the mobiledevice, to a base station of the wireless communication system; andretransmitting the LPP PDU to the base station when the transmission isfailed.
 3. The method of claim 2, wherein initiating the transmissionfor transmitting the PDU of the LPP layer to the base station of thewireless communication system comprises: failing in transmitting the LPPPDU to the base station when a re-establishment of a first communicationlayer lower than the LPP layer, a handover, or a radio resource control(RRC) connection re-establishment of the mobile device occurs; andwherein retransmitting the LPP PDU to the base station when thetransmission is failed comprises: retransmitting the LPP PDU to the basestation after the re-establishment of the first communication layer, thehandover, or the RRC connection re-establishment is performedsuccessfully.
 4. The method of claim 3, wherein retransmitting the LPPPDU to the base station after the re-establishment of the firstcommunication, the handover, or the RRC connection re-establishment isperformed successfully comprises: utilizing a RRC layer of the mobiledevice to indicate to the LPP layer that the LPP PDU transmission isfailed; utilizing the RRC layer of the mobile device to indicate to theLPP layer that the re-establishment of the first communication layer,the handover, or the RRC connection re-establishment is performedsuccessfully; and utilizing the LPP layer to retransmit the LPP PDU whenthe RRC layer is utilized to indicate to the LPP layer that there-establishment of the first communication layer, the handover, or theRRC connection re-establishment is performed successfully; or comprise:utilizing a packet data convergence protocol (PDCP) layer of the mobiledevice to retransmit the LPP PDU after the re-establishment of the firstcommunication layer of the mobile device, the handover, or the RRCconnection re-establishment is performed successfully.
 5. The method ofclaim 2, wherein retransmitting the LPP PDU to the base station when thetransmission is failed comprises: starting a timer of the LPP layer whenthe LPP layer transmits the LPP PDU to the first communication layer;and utilizing the LPP layer to retransmit the LPP PDU when the timer isexpired.
 6. The method of claim 5, further comprising: utilizing a RRClayer of the mobile device to indicate to the LPP layer that the LPP PDUtransmission is successfully performed, when the RRC layer transmits theLPP PDU successfully to a second communication layer lower than the RRClayer; and stopping the timer.
 7. A method of handling long termevaluation positioning protocol (LPP) data for a network in a wirelesscommunication system, the method comprising: receiving a protocol dataunit (PDU) of a long term evaluation positioning protocol (LPP) layer ofan evolved serving mobile location centre (E-SMLC) of the wirelesscommunication system; initiating a transmission for transmitting the LPPPDU to a mobile device of the wireless communication system; andindicating that the LPP PDU transmission is failed to the E-SMLC whenthe transmission is failed.
 8. The method of claim 7, wherein initiatingthe transmission for transmitting the LPP PDU to the mobile device ofthe wireless communication system comprises: failing in transmitting theLPP PDU to the mobile device when a re-establishment of a communicationlayer lower than the LPP layer, a handover, or a radio resource control(RRC) connection re-establishment of the mobile device occurs.
 9. Themethod of claim 8, further comprising: after the mobile device performsthe handover, or the RRC connection re-establishment successfully, notindicating that the LPP PDU transmission is failed to the E-SMLC whenthe mobile device reconnects to a first base station of the network; andretransmitting the LPP PDU to the mobile device after the mobile deviceperforms the re-establishment of the communication layer lower than theLPP layer, the handover, or the RRC connection re-establishmentsuccessfully .
 10. The method of claim 9, wherein retransmitting the LPPPDU to the mobile device after the mobile device performs there-establishment of the communication layer lower than the LPP layer,the handover, or the RRC connection re-establishment successfullycomprises: after the mobile device performs the re-establishment of thecommunication layer lower than the LPP layer, the handover, or the RRCconnection re-establishment successfully, utilizing a packet dataconvergence protocol (PDCP) layer of the first base station toretransmit the LPP PDU to the mobile device.
 11. The method of claim 8,further comprising: forwarding the LPP PDU to a second base station ofthe network when the mobile device performs the handover or the RRCconnection re-establishment to the second base station, so that thesecond base station retransmits the LPP PDU to the mobile device afterthe mobile device performs the re-establishment of the communicationlayer lower than the LPP layer, the handover, or the RRC connectionre-establishment successfully.
 12. A method of handling long termevaluation positioning protocol (LPP) data for a network in a wirelesscommunication system, the method comprising: initiating a transmissionfor transmitting a protocol data unit (PDU) of a long term evaluationpositioning protocol (LPP) layer to a mobile device of the wirelesscommunication system via a first base station of the wirelesscommunication system when a re-establishment of the communication layerlower than the LPP layer, a handover, or a radio resource control (RRC)connection re-establishment occurs; and retransmitting the LPP PDU tothe mobile device via a second base station when the transmission isfailed, wherein the mobile device connects to the second base stationafter the mobile device performs the handover, or the RRC connectionre-establishment successfully.
 13. A communication device of a wirelesscommunication system for handling long term evaluation positioningprotocol (LPP) data, the communication device comprising: means forgenerating a first message of a non-access stratum (NAS) layer of thecommunication device and a second message of a long term evaluationpositioning protocol (LPP) layer of the communication device; and meansfor setting that the first message of the NAS layer has highertransmission priority than the second message of the LPP layer.
 14. Thecommunication device of claim 13, further comprising: means fortransmitting the first message and the second message on a signalingradio bearer 2 (SRB2); or means for establishing a signaling radiobearer (SRB) which has lower logical channel priority than the SRB2, andthen transmitting the second message on the SRB; or means fortransmitting the first message and the second message on a signalingradio bearer 1 (SRB1) when only the SRB1 is established; or means fortransmitting the first message on the SRB1 and the second message on theSRB2, where the SRB1 has higher logical channel priority than the SRB2.15. The communication device of claim 14, wherein the means forestablishing the SRB which has lower logical channel priority than theSRB2 comprises: means for receiving a radio resource control (RRC)message for the SRB configuration from a network of the wirelesscommunication system when the communication device is a mobile device;and means for establishing the SRB according to the received RRCmessage.
 16. A mobile device of a wireless communication system forhandling long term evaluation positioning protocol (LPP) data, themobile device comprising: means for initiating a transmission fortransmitting a protocol data unit (PDU) of a long term evaluationpositioning protocol (LPP) layer of the mobile device, to a base stationof the wireless communication system; and means for retransmitting theLPP PDU to the base station when the transmission is failed.
 17. Themobile device of claim 16, wherein the means for initiating thetransmission for transmitting the PDU of the LPP layer to the basestation of the wireless communication system comprises: means forfailing in transmitting the LPP PDU to the base station when are-establishment of a first communication layer lower than the LPPlayer, a handover, or a radio resource control (RRC) connectionre-establishment of the mobile device occurs.
 18. The mobile device ofclaim 17, wherein the means for retransmitting the LPP PDU to the basestation when the transmission is failed comprises: means forretransmitting the LPP PDU to the base station after there-establishment of the first communication layer, the handover, or theRRC connection re-establishment is performed successfully.
 19. Themobile device of claim 18, wherein the means for retransmitting the LPPPDU to the base station after the re-establishment of the firstcommunication, the handover, or the RRC connection re-establishment isperformed successfully comprises: means for utilizing a RRC layer of themobile device to indicate to the LPP layer that the LPP PDU transmissionis failed; means for utilizing a RRC layer of the mobile device toindicate to the LPP layer that the re-establishment of the firstcommunication layer, the handover, or the RRC connectionre-establishment is performed successfully; and means for utilizing theLPP layer to retransmit the LPP PDU when the RRC layer is utilized toindicate to the LPP layer that the re-establishment of the firstcommunication layer, the handover, or the RRC connectionre-establishment is performed successfully; or comprise: means forutilizing a packet data convergence protocol (PDCP) layer to retransmitthe LPP PDU after the re-establishment of the first communication layerof the mobile device, the handover, or the RRC connectionre-establishment is performed successfully.
 20. The mobile device ofclaim 18, wherein the means for retransmitting the LPP PDU to the basestation when the transmission is failed comprises: means for starting atimer of the LPP layer when the LPP layer transmits the LPP PDU to thefirst communication layer; and means for utilizing the LPP layer toretransmit the LPP PDU when the timer is expired.
 21. The mobile deviceof claim 20, further comprising: means for utilizing a RRC layer of themobile device to indicate to the LPP layer that the LPP PDU transmissionis successfully performed, when the RRC layer transmits the LPP PDUsuccessfully to a second communication layer lower than the RRC layer;and means for stopping the timer.
 22. A network of a wirelesscommunication system for handling long term evaluation positioningprotocol (LPP) data, the network comprising: means for receiving aprotocol data unit (PDU) of a long term evaluation positioning protocol(LPP) layer of an evolved serving mobile location centre (E-SMLC) of thewireless communication system; means for initiating a transmission fortransmitting the LPP PDU to a mobile device of the wirelesscommunication system; and means for indicating that the LPP PDUtransmission is failed to the E-SMLC when the transmission is failed.23. The network of claim 22, wherein the means for initiating thetransmission for transmitting the LPP PDU to the mobile device of thewireless communication system comprises: means for failing intransmitting the LPP PDU to the mobile device when a re-establishment ofa communication layer lower than the LPP layer, a handover, or a radioresource control (RRC) connection re-establishment of the mobile deviceoccurs.
 24. The network of claim 23, further comprising: means for notindicating that the LPP PDU transmission is failed to the E-SMLC whenthe mobile device reconnects to a first base station of the networkafter the mobile device performs the handover, or the RRC connectionre-establishment successfully; and means for retransmitting the LPP PDUto the mobile device after the mobile device performs there-establishment of the communication layer lower than the LPP layer,the handover, or the RRC connection re-establishment successfully. 25.The network of claim 24, wherein the means for retransmitting the LPPPDU to the mobile device after the mobile device performs there-establishment of the communication layer lower than the LPP layer,the handover, or the RRC connection re-establishment successfullycomprises: means for utilizing a packet data convergence protocol (PDCP)layer of the first base station to retransmit the LPP PDU to the mobiledevice after the mobile device performs the re-establishment of thecommunication layer lower than the LPP layer, the handover, or the RRCconnection re-establishment successfully.
 26. The network of claim 23,further comprising: means for forwarding the LPP PDU to a second basestation of the network when the mobile device performs the handover orthe RRC connection re-establishment to the second base station, so thatthe second base station retransmits the LPP PDU to the mobile deviceafter the mobile device performs the re-establishment of thecommunication layer lower than the LPP layer, the handover, or the RRCconnection re-establishment successfully.
 27. A network of a wirelesscommunication system for handling long term evaluation positioningprotocol (LPP) data, the network comprising: means for initiating atransmission for transmitting a protocol data unit (PDU) of a long termevaluation positioning protocol (LPP) layer to a mobile device of thewireless communication system via a first base station of the wirelesscommunication system when a re-establishment of the communication layerlower than the LPP layer, a handover, or a radio resource control (RRC)connection re-establishment occurs; and means for retransmitting the LPPPDU to the mobile device via a second base station when the transmissionis failed, wherein the mobile device connects to the second base stationafter the mobile device performs the handover, or the RRC connectionre-establishment successfully.